Jest is a javascript testing framework designed to ensure correctness of any javascript codebase. You can run jest directly from the cli (if it's globally available in your path, e.g. By yarn global add jest or npm install jest --global) with a variety of useful options.
Jest documentation uses yarn commands, but npm will also work. In your test files, jest puts each of these methods and objects into the global environment. Babel-jest is automatically installed when installing jest and will automatically transform files if a babel configuration exists in your project.
Jest is a universal testing platform, with the ability to adapt to any javascript library or framework. In this section, we'd like to link to community posts and articles about integrating jest into popular js libraries. You can cherry pick specific features of jest and use them as standalone packages.
Learn how to get started with jest. Learn how to configure jest. Reminders that with class components, we expect jest to be used to test props and not methods directly.
Now let's use react's test renderer and jest's. The jest command line runner has a number of useful options. You can run jest --help to view all available options.
